Internalizing problems, including depression and anxiety, have consistently been associated with dysregulation of the hypothalamus-pituitary-adrenal (HPA) axis, the major physiological stress response system. The proposed research project will explore relations between late adolescents' styles of coping with distress and their HPA reactivity to negotiating conflict with their romantic partners. Couples are asked to discuss and attempt to resolve a conflictual issue that they have had disagreed about in the past month. HPA reactivity is assessed using samples of salivary cortisol, a primary hormonal product of the HPA system. A basal salivary cortisol sample, a pre-task anticipatory sample, and 5 post-task samples (10, 20, 30, 45 and 60 minutes after the conflict) are collected. Hierarchical Linear Modeling will be used to predict adolescents' HPA reactivity from their self-reported use of problem-focused coping, emotional approach coping, distraction, rumination, and avoidant coping strategies. Identifying coping strategies that are associated with dysregulated and healthy stress responses has important implications for understanding the development of internalizing problems and may be useful for developing interventions for at-risk youth.